Lidding it would be great, but removing it would be better. There are loads of people who live in the suburbs north and south of Seattle and expect to be able to drive 20-30 miles each way day-in-day-out to commute. If the city continues to grow, this simply isn't tenable in the long run, because you can't grow highway capacity forever; they would no longer be able to do this, which would be good. Just rip the band-aid off.